A novel oligomer PPV derivative (OPPV) is reported, which is designed to contain the oxadiazole functionsegment in the main chain. Photoluminescence of the OPPV thin film originates from aggregated states. In adouble layer device consisting of poly phenylene vinylene (PPV) and OPPV, emission only from PPV layer wasobserved and the efficiency of the device was improved by about one order of magnitude compared with the single layer PPV device, this indicates the electron transport characteristic of OPPV. In the OPPV/Tb complex device,OPPV functions as the hole transport layer. A possible explanation is proposed.